A cold-cathode fluorescent lamp driver circuit with synchronous primary-side dimming control

Abstract

A novel synchronous primary-side dimming control scheme is proposed and tested for a cold-cathode fluorescent lamp (CCFL) driver circuit for liquid crystal display (LCD) backlight illumination display applications. This new control scheme features high efficiency, even-dimming sensitive adjustment, even-brightness control for a two-lamp system, less lamp flickering problems, stable feedback control and simplicity. An analysis of the circuit is given, from which a design example is presented.